A 70-year-old man told gardai he was acting in self defence when he strangled to death his husband-to-be, a murder trial has heard.

Conor Devally SC opened the trial of Desmond Duffy at the Central Criminal Court, telling a jury of six men and six women that the accused and the deceased, Desmond Sullivan (59), shared a home at Somerville Park in Rathmines, Dublin 6.

Mr Duffy has pleaded not guilty to Mr Sullivan's murder at their home on May 23, 2016.

Mr Devally explained that as they share a first name, the deceased was known to friends as Little Des, the accused as Big Des. They were in a civil partnership and due to be married in July 2017.

They were drinking partners, Mr Devally said, and partners in life.

On May 23, 2016, after "a fair amount of drinking" they went home.

There was a row and in the wake of that Mr Sullivan lay at the threshold of the kitchen and downstairs bathroom.

Mr Duffy then called his partner's nephew, Garda Maurice Ward, who found the body and called gardai and emergency services.

When he spoke to gardai, Mr Devally said the accused suggested he was acting in self defence, telling them he was not the aggressor and that he fended off an attack by squeezing Mr Sullivan, strangling his airways and causing his death.

Gda Ward gave evidence today, telling Mr Devally that he received a call from the accused at about 10.15pm asking him to call over. He asked, "is everything ok?" and Mr Duffy responded: "No, it's not ok."

Gda Ward arrived at the house at about 10.45pm. Mr Duffy was "shook" and apologised for bringing him there.

Gda Ward said he could tell from Mr Duffy's demeanour that something serious had happened and asked if an ambulance was needed. Mr Duffy said: "Yes, I think so."

Gda Ward asked if Mr Sullivan was dead and he replied again, "Yes, I think so."

In the kitchen Gda Ward saw the body in a doorway leading to the bathroom and knew he had been dead for some time. When he asked Mr Duffy what happened the accused told him they had a physical fight and raised his hands to his neck area, saying that he put his hands up and Mr Sullivan fell to the ground.

Under cross examination Gda Ward agreed with defence counsel Caroline Biggs SC that he had known the accused and deceased since 1996 and that the accused always seemed to be a gentle person.

He met them three or four times a year and never saw him being physically or verbally aggressive. Both men were intelligent, he said, and great company.

He added: "They were a pleasure to be around. You wouldn't be short of conversation with them."

He further accepted that they were due to be married in July 2017.

The trial will continue in front of the jury and Justice Paul McDermott tomorrow.